Manufacture of ebonite and vulcanite.



higher temperature hereinafter mentioned.

OTTO CLAUDE IMMISQH, OF FINCHLEY, ENGLAND.

MANUFACTURE OF EBONITE AND VULCANITE.

No Drawing.

Specification of Letters Patent.

Patented Oct. 19, 1909.

Application filed February 19, 1909. Serial No. 478,963.

To all whom it may concern:

Be it known that I, Orro CLAUDE IM- )IISCH, a subject of the King ofGreat Britain, residing at 4 Woodside Park road, Finchley, Middlesex,England, have invented new and useful Improvements in the Manufacture ofEbonite and Vulcanite; and I do hereby declare that the following is afull, clear, and exact description of the invention, which will enableothers skilled in the art to which it appertains to make and use thesame.

My invention relates to the manufacture of goods of various kinds andshapes from old or waste ebonite or vulcanite and to that process ofmanufacture wherein the waste material, in a divided state, is subjectedto heat and pressure, the object of my invention being to producearticles which possess all the qualities ofthe original material. Theprocess by which this result is attained is as follows :-The wasteebonite is reduced to small particles in such a Way that the bulk unitof weight of the reduced material is, when not compressed, considerablylarger than that obtained by pulverizing or grinding so that they are ina friable condition. Turnings or shavings of the material are suitablefor my purpose. The reduced material is placed in a mold, preferablycold, having larger capacity than the column of the article required,say in the direction of its longest dimension. By suitable means thematerial in the mold is then subjected to a high pressure and, by theuse of a clamp or slmilar means, the pressure is retained; The mold isthen placed in an oven and slowly reheated to a temperature of about 280Fahrenheit for a time depending upon the dimensions and weight of themold. This preliminary pressing and heating may in some instances berepeated with advantage before subjecting the material to the l/Vhilestill hot, the mold is removed from the oven and, while the mold iscooling, the material is further compressed so that its volume shall beapproximately that of the required article. The mold is then clamped andreplaced inthe oven and heated to a temperature of over 400 Fahrenheit,the temperature varying with the quality of the waste ebonite, and thetime depending upon theweight and dimensions of the mold as "about aquarter of imperfect.

before mentioned. After this temperature has been attained, the mold isremoved from the oven and allowed to cool down slowly, when the clampmay be removed and the article taken out of the mold.

In the case of the finished article weighing good results by firstsubjecting the material in the mold while cold, to a pressure of 600retaining this pressure by means of a clamp, raising the temperature ofthe mold to 280 F. in 30 minutes. I then remove the mold from the ovenand subject the material to a pressure between 500 and atmospheres and,

600 atmospheres, and maintain this pressure means for about 15 minutes,by

the mold should have cooled down considerably. I then tighten the clampand replace the mold in the oven, and gradually heat it to a temperatureof 440 F. in about 40 minutes. I then remove the mold from the oven, andallow it to -cool slowly, after which I open the mold and remove thearticle.

by suitable which time a pound I have obtained In the manufacture ofsmall articles where the density of the ebonite is not of importance,the waste material can be reformed without the preliminary heatingreferred to above :the material while under pressure in a clamped moldbeing slowly heated to a temperature of between 400 and 440 Fah., butunless the initial pressure exceeds the pressure stated above, thedensity of the finished a temperature of between 400 and 440 F., inorder that the structure of the reformed ebonite, as shown on fracture,shall be similar to that of the original material. As is well knownsulfur, when heated to a temperature of between 400 and 440 Fah.,undergoes a physical change becoming soft and pasty, but recovering itsoriginal hardness when cooled slowly. The same physical change occurs inebonite at about the same temperature. The'efi'ect of the high pressure,due to the expanding force of the confined material (when heated in aclosed mold) on the particles forming such mass when in the plasticstate,- causes" complete coalescence of the particles.

In order to avoid injuries to the mold through any exceptional pressurearising from the expansion of the heated material article will be lowerand the structure I have found it necessary to use a which consists inreducing such waste ma- I find that, in the manufactureof articles oflarge dimensions, it is desirable to provide means, such as a spring fortaking up any excessive pressure above that which the clamp is intendedto retain.

Having now particularly described and ascertained the nature of my saidinvention and in What manner the same is to be performed, I declare thatwhat I claim is 1. In the manufacture of articles from waste ebonite andvulcanite, the process terial to a condition in which the individualunits are considerably larger than those of a granulated or pulverizedcondition, placing such material in a mold and subjecting the same tohigh pressure, then subjecting the mold and its compressed contents to atemperature of about 280 F., then further compressing the material toapproximately the volume required for the finished article and thenagain subjecting the mold and its I compressed contents to a temperatureof about 400 F.

2. In the manufacture ofarticles from waste ebonite and vulcanite, theprocess which consists in reducing such waste material to a condition inwhich the individual units are considerably larger than those ofa'granulated or pulverized condition, placing such material in a moldand subjecting the same to high pressure without heat, then subjectingthe mold and its compressed contents to a temperature of about 280 F.,then removing the mold from the influence of heat and While coolingsubjecting the material in the mold to a further compression and thenagain subjecting the mold and its com-' pressed contents to atemperature of about OTTQ CLAUDE IMMISCH. Witnesses:

JOHN E. BOUSFIELD, C. G. REDFERN.

